1. Field of the Invention
Embodiments of the present invention generally relate to semiconductor processing equipment.
2. Description of the Related Art
The throughput of semiconductor wafers in semiconductor process equipment is often limited by the ability to supply wafer carriers (also referred to as FOUPs, Front Opening Unified Pods) containing unprocessed wafers to the process equipment. To improve throughput a wafer buffering system may be utilized to store and buffer FOUPS during wafer processing operations.
Conventional wafer buffering systems may include, for example, multiple load ports where a wafer carrier is placed at each load port and is removed after all wafers have been processed. These systems have large footprints, taking up a sizeable amount of floor space. Other systems may include vertically oriented apparatus where the wafers are buffered for processing in a narrower footprint, but typically require several transfer mechanisms, such as transfer robots, to operate effectively. These systems are prohibitively expensive to implement.
Thus, there is a need for a wafer buffering system which has a high throughput, yet is scalable and cost effective.